Electric switch.



UNITED STATES .PATENT OFFICE.

WILLIAM '.r. PRINGLE, or PHILDELPHIA', rnnnsvnvnma.r

ELECTRIC SWITCH.

Specication of Letters Patent. j )adjnte'dl Jan. 3i, 191i.

Appncatian med April 7, 1909. serial Nn.- 488,463.

To all whom it may concern:

Be' it known that I, VILLIAM T. PRINGLE, of Philadelphia, in the State of Pennsylvania, have invented 'a certain new and useful Improvement -in Electric Switches, whereof the following is a specification, reference being had to the accompanying drawings. A

My invention is conveniently applicable to ordinary knife switches, or switches of any type operated by mcansot a lever, and may he employed with special advantage in theaters or other installatons Where such switches are covered by a siield or casing through which the levers project and the latter are apt to be accidentally displaced.

As hereinafter described, my invention includes a device which may be supported by a shield or casing covering a switch, and independently ofi the latter, hut in such relation to= the switch lever as to detain the latter in either o't'its extreme positions and4 prevent said lever from remaining in an intermediate position. As described, said lever controlling devlce conveniently in- 'cludes a plate having a slot through which the lever extends, and two opposed resilient or spring pressed members, one of which serves to normally detain said lever in either 9i its extreme positions, and the other of which in coperation with the first member serves to prevent said lever from remaining in an intermediate position.

My invention comprises the various novel features of construction and arrangement. hereinafter more definitely specified and claimed.

In the drawings; Figure I isa fragmentary vertical sectional view of a casing, showing an ordinary knife switch with my invention applied thereto, the switch lever being in the open position. Fig. IIis a fragmentary sectional view similar to Fig. I, but showing the switch lever in closed position. Fig. III is an inner face View of the lever controlling device Vshown in Figs. I and II, .the opposed movable members thereof being resilient. -Fig. IV is a view simi lar to Fig. III, but shovvincr a modified form of the invention wherein l e opposed mov able members are rigid but adaptedto oseillate toward and away .from each other.

.In said figures.; 11s-a casing mclosmg a switch having'the insulating base 2, termi#- bar 6, are mounted to oscllate on the pivots 7 in said brackets 4, when operated by the lever 9, provided with the handle l0. Said lever 9 extends through the slot 12in the plate 13 of the lever controlling device, which isset in a suitable recess in said casing 1, to which it is rigidly connected by screws 15 extending through the openings- 1G, in said plate. As shown in Flg. III. said plate 13 is provided with` the boss 18, which supports the two opposed relatively movable members 20 and-21, which are conveniently formed of spring metal. As indicategl, said member 20 is so shaped as to hear upon the lever 9 and normally retain it in either of its extreme positions in said slot 12. Said member 21 is so shaped as to rojecl into the path of said lever interme late. of its extremepositions and in opposition to said member 20, so as to force said lever 9 away from .its intermediate position in either direction of 1ts traverse. It is to be understood that the coperative eiect of the opposed relatively 'imovable members 20 and 2L aforesaid is' ,such that an appreciable manual eiiort is required to shift the lever E) past its intermediate position, but when past. said position 'said members, and particularly the member 21., tend to throw said lever to its extreme position, and, said member 20 then' retains said lever in .said cxtreme position until it is again manually shifted.

The form of my invention shown in Fig Ivcomprises opposed relatively movable membersI 23and 211 having the respec- Ytive functions of the members 20 and 21 labove described. However, said members 23 and 24 are rigid butmounted to oscillate upon respective piv'ots 25 and 2G extending from their supporting plate 27 The upper ends of said members 23 and 24 are connect- 'ed bythe spring 28 which normally presses them into the relative position shownsaid spring being conveniently detachably enga ed with said members as indicated.

t may be observed that it is characteristic f both forms of my invention above described that a device is provided which isprimarily separate -and distinct from the switch mechanism so that it is capable of'being mounted in anydesired relation with the swltch lever in accordance with the onstruction of the easing mclosmg the sw1tch mecha nism, but, when said device` is arranged incoperative relation with the switch mecharate switch mechanism.

j anism having an oscillatory operating lever;

"switch'in both directions'but prevents the tures of' my invention asldefined in the apof 4a device distinct from the saidlswitch -dependently thereof; having op osed relato normally retain said, lever in either of the nism'asabove described it hasthe elect fof not only producing a snap action of the switch mechanism from being left in an intermediate position wherein the terminals and blades might be damaged by arcing. Moreover, it maybe observed that my inventionaforesaid, has theA` economical advantage that it is applicable to switches of the ordinary types, to effect an-operation which it has hitherto been only possible 4to eliect. at greater expense, with -more elabo- I do not desire to limit myself to the precise details of the constructionend.arranger ment above described, as it is obvious that various modifications may be -made therein without'departing from the essential feapended claims.

1.. The combination with a switch meehanism having'an oscillatory opera tinglever;

mechanism and arranged to b'e supported intively movable members arrange to' engagev said leverand effect a sna'p action thereof; one of saldmovable members belng arranged extreme positions of the latter.

2. The combination with-aswitch meehof a device distinct from the saidA switch meehanism and arranged to be supported i'A vindependently thereof; having opposed relatively movab members arranged to engage said lever and eieet a snap action thereof; one of said movable membersbeing arranged to normally retain said lever in either of the extreme positionsof the latter; and, the other of said movable members being arranged to bear upon said lever only whenl the latter is in an intermediate position.

3. 'The combination with a switch meeh-` anism-ha'ving an oscillatory operating lever; of a device distinct from the said switch mechanism and arranged to be supported independently thereof; having opposed relatively movable members arranged to engage Isaid lever and eieet a snap action thereof;

one of said movable members being arranged Kto normally retain said lever in either of the "extreme positions of the latter; and, the

L. W. HALL, W. W. BEA'rrr. 

